Studying Insects can Show how Human Projects Impact Ecosystems

As the largest dam removal in U.S. history brought Pacific salmon back to Washington state’s Elwha River for the first time in nearly a century, scientists were considering the changing ecosystem’s impact on those foundational Elwha Valley dwellers: insects.

In the spring, entomology professor Richard Zack brought to Washington State University some millions of specimens collected before removal of the 100-year-old dams in Olympic National Park.

He is leading a project to sort, identify and curate the insects and create a database to provide insight into how the Elwha Valley ecosystem might change in the next several decades. Changes in insects will play a key role in how the new ecosystem develops.

“The Elwha is a fabulous research opportunity because it is a rare before and after study,” Zack said. “Understanding what is expected to be a 30- to 40-year trajectory of recovery will require comparing the pre-removal ecosystem with species changes and abundances as recovery proceeds.”

Bioblitz for bugs

The insect collection was part of a long-term, large scale project conducted by researchers from the University of Washington and the National Park Service, said Jerry Freilich, research coordinator for Olympic National Park and partner on the project. The ATBI, or all taxa biotic inventory, aimed to collect aquatic and riparian invertebrates and non-vascular plants in the Elwha drainage.

“When removal of the dams began we knew everything was going to start changing,” Freilich said. Park Service biologists were already looking at larger plants and animals in the Elwha Valley “but a study was needed to find and identify the smaller, often overlooked organisms that make up the ecosystems foundation.”

This is one of the first studies that will not only look at the more “charismatic meagafauna,” Freilich said, but “also the microfauna.”

After the collections were made, Freilich connected with Zack to begin classifying the insects.

“If you want entomology experts in the Pacific Northwest, WSU is where you go,” he said.

Training future scientists

But where do you start when you have hundreds of thousands of bugs to organize?

She and fellow student Noah Austin, a WSU double major in physics and music, work in a lab in the entomology department where they sort, prepare and identify the aquatic bugs, caddisflies, mayflies, stoneflies, true flies and beetles. Eventually, most of these specimens will be sent to specialists for specific identification.

“Noah is a pinning machine,” Hamada said as they worked in the lab. While still in the beginning stages of sorting the specimens by order or family, they each have pinned hundreds of insects.

The project serves as a training opportunity for young scientists. It also will be the first to provide information on the biodiversity of Olympic National Park, one of the most geographically interesting regions of the U.S., said Zack.

Preparing to look back

The Elwha dams, built in the early 1900s, created still reservoirs of water that changed the river system dramatically. Now that water is again free-flowing, river- and stream-dwelling insects are expected to return to the valley, Zack said.

Next spring at Elwha, Zack will meet with entomologists, biologists, researchers and other partners on the project, including those classifying butterflies and spiders, to discuss how they can best use the collections to understand the impacts that dam removal has on ecosystems.

The insects collected for the project will join the 3 million specimens already housed at the M.T. James Entomological Collection at WSU. The project is funded by a two-year $30,000 grant from the Katz Memorial Foundation and conducted through the WSU Agricultural Research Center in the College of Agricultural, Human and Natural Resource Sciences.